Some have already written off McLaren on the basis that not evolving the winning 2012 car in favour of a radical machine for this season was a grave mistake that has netted the famous British team just 4 points so far this season.
Jenson Button, however, told the Mirror he thinks a title tilt is still "definitely" on.
"It's a massive turnaround for us," he said, referring to the progress made in mere days between Australia and Malaysia.
"Most of the race in Sepang we were quicker than the Lotus. Most of the race we were quicker than Ferrari," he said.
"I have gone from being pretty down in Melbourne to being a lot more positive."
And team boss Martin Whitmarsh is quoted by Speed Week: "I would be very disappointed if we did not make a further step in China."
Already competitive is Ferrari, where Felipe Massa is now right back on the pace after a lean period of form, and Fernando Alonso was a favourite for victory in Malaysia until his first-lap dramas.
"Red Bull, in my opinion, is still the strongest team at the moment," team boss Stefano Domenicali is quoted by Corriere della Sport.
"Mercedes has made progress, Lotus is very competitive. The season will be interesting and challenging, but no doubt we will be there among the best."
Also confident is Lewis Hamilton, having switched from McLaren over the winter and already collecting 25 points compared to championship leader Sebastian Vettel's 40.
In Malaysia, he put his Mercedes on the podium, behind the warring Red Bulls.
But, referring to the Sepang race, Hamilton insisted: "For a time I was able to drive on the pace of the Red Bulls and it felt great."
Ultimately, he had to drop his pace to save fuel, but if not for that issue, "the situation would have been different. I am sure," the Briton is quoted by Finland's Turun Sanomat.
"If we continue on this path, we will be able to win at some point in the season," added Hamilton.